Bicycle crank and bearing.



No. 630,072. Pa'tentod Aug. I, I899. .1. H. RATHBUN.

BICYCLE CRANK AND BEARING.

(APPHGIJOIL filed Oct. 14, 1897.)

(No Model.)

, UNrrnn STATES PATENT Crusoe.

JOHN H. RATHBUN, OF MILWAUKEE, VISCONSIN.

BICYCLE CRANK AND BEARING.-

SPECIFICATION forming part of Letters Patent No. 630 072, dated August1, 1899.

Application filed October 14, 1897. Serial No. 655,166. (No model.)

To all whom it may concern.- Be it known that I, JOHN H. RATHBUN, ofMilwaukee, in the county of Milwaukee and State of Wisconsin, haveinvented certain new and useful Improvements in Bicycle Cranks andBearings; and I do hereby declare that the following is a full, clear,and exact description of the invention, which will enable others skilledin the art to which it pertains to make and use the same, referencebeing had to the accompanying drawings, and to the letters of referencemarked thereon,which form a part of this specification.

The main objects of my invention are to provide a rigid and secureconnection between the crank arms and axle, at the same time producing alight construction of neat symmetrical appearance, to provide for easyand accurate adjustment of the ball-bearings, to facilitate the removalof the axle from the hanger and access to the ball-bearings, to excludedust and dirt from the bearings, and generally to improve theconstruction and operation of devices of this class.

It consists of certain novel features in the construction andarrangement of the crankarms, axle, and bearings, as hereinafterparticularly described, and pointed out in the claims.

In the accompanying drawings like letters designate the same parts inboth figures.

Figure 1 is an axial section of a crankhanger, axle, and bearin gsembodying my improvements; and Fig. 2 is an end view of the same asviewed from the left with reference to Fig. 1.

A designates a tubular crank-hanger in the ends of which are fitted ballraces or cups B B, abutting at their inner ends against internalshoulders a a and projecting at their outer ends beyond the ends of saidhanger A. The ball-races are provided with washers b h, sprung intointernal grooves in their outer ends to hold the balls 0 O therein whenthe crank-axle,with the opposing bearings thereon, is removed.

D D are the crank-arms formed on the inner faces of their hubs withannular flanges d d of the same internal diameter as the ends of thehanger A. The projecting ends of the ball-races 13 fit loosely inside ofthe flanges d d, and with them and the washers b I) serve to oppositeend, which is fitted to be expanded in the bore or hole of the crank-armD. The hole in this arm is elongated, as shown in Fig. 2, squared orotherwise shaped, so as to prevent the crank-arm from turning on theaxle when the latter is expanded therein. The bore in the split end ofthe axle is made tapering or flaring, increasing in diameter outwardlytoward the end of the axle.

F is a pin tapered at one end to fit the tapered bore of the axle,threaded at its oppo site end, and provided with a nut f, which ispreferably countersunk into the hub of arm D.

G G are cone-bearings fitted one upon the axle E next to the hub of armD and the other upon an inwardly-projecting flange (l on the hub of armD, around the hole therein.

The hub of the arm D is formed with a seat, flange, or ears d d for theattachment of the sprocket-wheel. To detach and remove the crank-armsand axle from the hanger and to gain access to the ball-bearings, thenut f is removed or loosened and the pin F driven out of engagement withthe split end of the axle, which is thus allowed to contract. The arm Dbeing thus released is easily withdrawn from the axle E, which can thenbe withdrawn from the hanger in the opposite direction with the arm D.The balls will he held in the hanger A by the washers Z). Free access isthus had to the bearings for cleaning and repairing the same. Theremoval of the sprocket-wheel and the substitution of a11- other ofdifferent size, which is often desirable, is also facilitated. When theparts are assembled, they are secured rigidly in place by driving thetapered pin F into and expanding the split end of the axle E, and thepin when driven into place is secured by screwing or tightening the nutf thereon. The ballbearings may be easily and quickly adjusted to takeup wear and play by loosening the pin F, setting the detachable arm D onaxle E toward the other arm D, and then securing it in place on theaxle, as hereinbefore explained.

My improved construction not only facilitates the removal of the cranksand axle, as

well as access to and adjustment of the ballbearings, butit is also easyand cheap to make and compact and symmetricalin design. The pin F beingplain or smooth and extending through the axle from end to end can bedriven in and out, the cones can be adjusted to take up play, and accesscan be readily had to the bearings for inspection and repairs withoutusing, special tools. The taperof the pin being gradual or ofconsiderable length, as shown, will of itself hold it securely in place,and the nut f may therefore be dispensed with, although as a safeguardagainst loss or accident it is perhaps advisable to retain it.

I do not Wish to be understood as limiting myself to the exact detailsherein shown and described, as they may be variously modified within thespirit and intended scope of my invention.

into and out of place, substantially as and 6 for the purposes setforth.

2. The combination with a crank-hanger provided in its ends withball-races,of a crankarm, a tubular axle rigidly attached at one end tothe hub of said arm and having its 35 bore extending through said hub,the oppo-' site end of said axle being split and having its boreincreasing in diameter outwardly, a detachable crank-arm having a holein its hub loosely fitted but so shaped as to prevent its 0 turning uponthe split end of said axle, a pin having a plain taper which is fittedto expand the split end of said axle in the hub of the detachable arm,and exposed when in .place at both ends of the axle for driving-.itpinand 45 out, cones, one of which is adjustable with the detachablecrank-arm,ballsinterposed be tween said cones and races, and means forretaining the balls in said races when the cones are removed,substantially as andfor 50 the purposes set forth.

In testimony that I claim the foregoingas my own I affix my signature invpresence of two witnesses.

JOHN H. RATHBUN.

WVitnesses:

lVIARY HAYES, CHAS. L. Goss.

